Method of and apparatus for drawing glass



A. E. SPINASSE METHOD OF AND APPARATUS FOR DRAWING GLASS Filed July 31 1926 Patented Nov. 24, 1931 UNITED STATES ARTHUR E. BPINASBE, MOUNT VERNON, OHIO, ABSIGNOB TO PITTSBURGH? GLASS COMPANY, A CORPORATION 01' PENNSYLVANIA,

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PATENT orrics METHOD 0! m AP PABA'I'US FOB DBLW H'G- ems Application fled July #1,

The present invention relates to improve,- ments'm method of an apparatus for drawing glass, and is a continuation in part of my similarly entitled co-pending application Serial 'No. 702 198, filed March 27 1924.

It is an ob'ect of the invention to provide an improve method and apparatus for drawingthe flat sheets of glass of substantially uniform thickness to and including the JD edges or mar 'n portions of the sheet, and to prevent the s rinking'inwardly of the edges of. the sheet as the sheet is drawn upwar 1y from the glass bath.

' With the foregoing and other objects in .15 view, the inventlon will be more fully described hereinafter, and will be more particularly pointed out in the claims appended hereto.

In the drawings, wherein like symbols refer ,9 to like or corresponding parts throughout the several views,

Figure 1 is a fragmentary top plan view of an apparatus constructed according to the present invention. 5 Figure 2 is a vertical section through the same.

Figure 3 is a perspective view of one of t e slot members emplo ed, and

Fi re 4 is an en view of the slot member so showing a portion of the glass bath and the glass sheet drawn therethrough.

Referring more particularly to the drawings, 1 designates one of the walls of the fur- 35 bath 2, and 3 represents the sheet of glass which is drawn upwardly from the bath by the sheet being drawn through the usua drawing rolls 26. .40 In Figure 1, shield members 27 are shown as placed parallel with the drawn glass sheet from the side portions of the sheet; In Figure 1, are also shown the'burner jets 30 to nace containing the molten glass of the glass an appropriate bait or other drawing too i 3 to cut oil and vregulate the furnace heat 45 locally increase or decrease the temperature 1920. Serial Io. 129,280.

in the re drawn. For convenience in illustration only one ed of the glass sheet is shownbut it will be un erstood that the same parts me be duplicated at the opposite edge of the s eet.

In accordance with the invention I rovide a slot member preferably. in'the cm of 'a plate, as shown more particularl Yin Fi ure 3. The plate is made with t e slot which slot is continued upwardly through the flanges or upstanding walls 12, which walls may be made as a part of the late if desired, and the plate may be made 0 metal, refractory clay or other material, The slot 7 ma be tapered if desired, narrowing upward y as indicated in Figure 4, and the slot may be wider at its outer open portion and ta r inwardly to the acute angle portion 1L I e plate .10 is perforated to receive the substantially vertical pivot bolt or pin 18 :3 which the plate may swing in a horizon plane for purposes of adjustment. The pin 18 ad'ustably secures the-plate 10 to the slotte link member 17 having the horizontal 1y disposed closed slot. link member 1'1 is secured to the pedestal or base member 16 having the vertical slot 18;? A bolt or pivot pin 21 is made'to pass throu h the slots and 19, whereby-to secure the ink member 17 i in adjusted position. The link member may: be adjusted up and down the pedestal or base,v member 16; it may be adjusted horizontally by virtue of the slot 20, or it may pivot in a substantially, vertical plane about the pin'or fulcrum 21. A heating and cooling means may be rovided in conjunction with the slot mem er if desired and in Figure 2, I illustrate one form of such device as consisting of the pipe bent upon itself and supported asupon the arm 15. The pipe is provided with a valve 25 in its induction branch to control the flow of the cool or hot. fluid medium thereto. The bight of the pipe may gion where theedges of the sheet are I be disposed the-portionof theplateio 10 or glass edge forming member which is close to or in contact with the edge of the sheet. It will be understood that although the side walls of the slot in the slot member are shown as straight, these walls may be rounded.

In the furnace .wall 1 is shown a pocket or channel 23 extending close to the point of generation of the edges of the sheet, and in this channel or pocket I dispose a pipe or nozzle 23 for conveying tern rature-afiecting medium of the ocket or c annel 24 under the control of a va ve 25 to increase and decrease the viscosity of the glass at the source of the drawn edge.

According to the improved method and operation of the apparatus, the glass .is gathered upon an appropriate tool from the rec natural surface of the hat 2, whereby glassof hi h quality may be dr wn, such as would be impracticable from dies or other devices up through which the glass is forced by hydrostatic pressure. At the base of the drawn sheet, when thus freely drawn, a thickened portion 4 naturally forms from the free surface of the bath. This portion forms in inverted V-shapet The slot members are placed above the bath of "'lass but in position to receive this thickened or wedge shaped portion of the lass at the edge and border portion of the orming sheet to partially reduce this thickened portion.

Necessarily a retarding frictional action upon the upwardly drawn glass takes place in the slot member resulting in the longitudinaI stretching of the border portions of the times the jet 23 may be put'into operation to sheet from the drawing tool to the slot members and this will also result in avoiding the transverse collapse or shrinkage of the sheet between the stretched border portions. Although it is not necessary that the glass adhere to the wall of the slot member, I prefer that the glass adhere thereto. The member 10 is preheated t-osecure and maintain such adhesion, such adhesion producin a better edge'and a better temper in the s eet. By use of the-pi e 45 or other device I am enabled to regu ate the degree of the adhesion to insure that the width of the sheet will be maintained uniform during drawing and to produce an edge of desired thickness. At

control the anchorage at the source of the drawn edge. With the upwardly extending flange 12, I secure an elongated upwardly ex- "tending slot for gradually reducing the thickness of the glass. 7

The late 10 serves to protect the drawn edge of the sheet from the radiating heat from the bath and the upwardly'extending wall 12 of the slot member, which projects above the plane of the plate 10, protects the drawn edges of the glass from the furnace heat, as well as to shape said edge in desired reduced thickness. By reason of the position of the preheated edge formin members, the same are maintained hot an therefore adhere to the drawn glass. B

From the above it will be understood that the edging members have-slots which engage the ta ring base of the drawn glass at a point b low the up er reduced end of the tapering base, said s ots bein narrower than the normal thickness of sai tapering base at: the point of en agement therewith to partially reduce the t ickness thereof, and being wider than the thickness of the finished edges of the sheet to create a dragging action at the contracted portion of the tapering base and at the same time preserving sufficient tapering thickness above the contracted portion to prevent injury to the draw.

What is claimed is 2- 1. In an apparatus for drawing sheet glass from the free surface of a bath'of molten glass at a articular level, a pair of hot plates at the e ges of the glass sheet being drawn from the bath, said plates having upwardly extending walls forming restricted slots throu h which the edges and border portions of t 6 sheet are upwardly drawn and reduced inthickness, and means for maintaining said plates in spaced fixed position above the surface of the bath.

2. In an apparatus for drawing sheet glass from the free surface of a bath of molten glass, edge forming members placed at opposite edges of the sheet in fixed position spaced above the bath of lass and. having 11 wardly converging walls or receivin the e ges and border portions of the glass s eet for acting to thin down such edges and to create a frictional resistance to the passage of the glass therethrough.

3. In anapparatus for drawin sheet glass from the free surface of a bat of molten. glass, edge forming members placed at opposite edges of the sheet in fixed postion spaced above the bath of glass and having u wardly converging walls for receivin the e ges and border portions of the glass s eet for acting to thin down such edges and to create a frictional resistance to the passage of the glass therethrough, and means to increase or decrease the degree of the frictional resistance.

4. In apparatus for drawing sheet glass from an open bath of molten glass at a particular level, an edging device comprising a hot horizontal metallic plate having upwardly converging walls spaced apart to form a slot opening through the end, to and bottom drawn glass from which the sheet forms ex tends in the slot and the walls forming the slot being adapted to contact and adhere with the side faces of the aforesaid border portion passing through the slot to shape said border use of the invention much breakage is e imlnated.

portion and prevent; the narrowing of the sheet, said plate being of such form as to protectand shield the forming border portions from the bath below and thereby promote the cooling of the same.

An edging member for drawing sheet glass from a bath of molten lass at a particular level, said edging mem r comprising'a fiat )late having spaced apartwa lls' project-- rom the plateto foinian open slot and being positioned spaced above the bath to receive the initially thickly drawn glass from which the sheet proper forms, the walls forming the slot bein adapted to contact and adhere with the si e face of the aforesaid bor: der portion to shape said border portion and prevent the narrowing of the sheet, and the said walls and plate being of such form to protect and shield the border portion of the Iiorming sheet from the glass below during drawing.

6. In apparatus for drawi-n sheet glass the bath for adherently embracin and shaping the border portion only of t e meniscus of the forming sheet, said device being of such form so as to shield the formin border portion of the sheet which passes tween and above said walls from the bath beneath said device, and means for modifying and controlling the temperature of the glass below said edging device.

In testimony whereofI aflix m si ature.

ARTHUR E. SP N SSE.

from the normal surface of the ath at a particular level, means for maintaining the desired width of the sheet comprising fixed hot member extending wholly spaced from and above the surface of the bath, said member having spaced apart walls extending up wardly and inwardly toward the sheet to form a slot through which the edge and border portions of the sheet may be adherently drawn to regulate the thickness thereof.

7. In apparatus for drawing sheet glass, the combination with a receptacle adapted to contain an open bath of molten glass at a particular level, a hot plate having upward- 1y extending walls forming a slot opening through its bottom, side and upper end, the walls forming the slot being adaptedto contact and adhere with the glass being drawn and being spaced apart so that the slot is wider at all points of contact with the glass than the finished thickness of the border portion of the sheet being drawn to receivethe border portion of the meniscus from which the sheet proper forms, means outside the receptacle for adjustably holding said plate in position spaced above the bath adjacent the walls of the receptacle to receive the aforesaid border portion of the meniscus, and means for drawing the sheet from the open bath with said border portion passing through the slot in adherent dragging contact against the walls forming the slot to 1 shape said border portion and prevent the narrowing of the sheet.

8. In apparatus for drawing sheet glass from an open bath at a particular level, a hot adherent edging device having upwardlyextending spaced-apart walls to form a passage therebetween open at top, bottom and one side with the side opening wider at all portions than the finished thickness of the sheet, said member being located wholly spaced from and fixed above the surface of Y 

